Fluid logic systems, diaphragm valve and parts therefore

ABSTRACT

A diaphragm valve adapted for use in logic circuits and parts therefor, particularly a diaphragm and a pilot valve. The valve comprises a housing having a cavity, a diaphragm forming at least one chamber in the cavity and having a passage closing element centrally thereof that can be moved to open and close one or more passageways by transverse movement of a flexible intermediate portion adjacent to the central portion. This transverse movement is caused by radial first class levers in response to differential forces on the diaphragm on opposite side of the fulcrum. In a preferred embodiment the fulcrum is formed by a partition wall integral with the diaphragm that forms an outer control pressure chamber and an inner supply pressure chamber having connection to a supply pressure line and load pressure line closable by said valve element to isolate it from the supply pressure line. Optionally the load pressure line may be dumped to atmosphere when it is so isolated. The control pressure chamber communicates with at least one and preferably three control pressure lines with a pilot valve to permit flow from only one control pressure line at any one time.

United States Patent Ginder, Jr.

Dec. 3, 1974 FLUID LOGIC SYSTEMS, DIAPHRAGM VALVE AND PARTS THEREFORE [76] Inventor: William F. Ginder, Jr., l6-D Seymour Village, Unionville, Conn. 06026 [22] Filed: July 5, 1973 [21 Appl. No.: 376,734

[52] U.S. Cl. 251/25, 92/98 R [51] Int. Cl. F16k 31/385 [58] Field of Search 251/25,6 l,61.1,61.2; 92/98 R, 102

[56] References Cited UNITED STATES PATENTS 3,080,887 3/1963 Brandenberg 251/61 X 3.l07,693 lO/l963 Puster et al..... 251/61 X 3,351,088 11/1967 Jensen 92/98 R X Primary Examinerl-lenry T. Klinksiek Attorney, Agent, or Firm-George H. Mortimer [57] ABSTRACT A diaphragm valve adapted for use in logic circuits and parts therefor, particularly a diaphragm and a pilot valve. The valve comprises a housing having a cavity, a diaphragm forming at least one chamber in the cavity and having a passage closing element centrally thereof that can be moved to open and close one or more passageways by transverse movement of a flexible intermediate portion adjacent to the central portion. This transverse movement is caused by radial first class levers in response to differential forces on the diaphragm on opposite side of the fulcrum. In a preferred embodiment the fulcrum is formed by a partition wall integral with the diaphragm that forms an outer control pressure chamber and an inner supply pressure chamber having connection to a supply pressure line and load pressure line closable by said valve element to isolate it from the supply pressure line. Optionally the load pressure line may be dumped to atmosphere when it is so isolated. The control pressure chamber communicates with at least one and preferably three control pressure lines with a pilot valve to permit flow from only one control pressure line at any one time.

37 Claims, 15 Drawing Figures FLUID LOGIC SYSTEMS, DIAPHRAGM VALVE AND PARTS THEREFORE BACKGROUND OF THE INVENTION Logic systems are known which utilize fluid diaphragm valves for various logic functions such as OR, AND, NOT, MEMORY, DIFFERENTIATOR and TIMING and the like. In general the fluid which is used to operate these valves is air and they are frequently referred to as pneumatic valves. These known valves have various deficiencies, a principal one being the complexity of the valve and the cost of manufacture. The invention disclosed and claimed herein overcomes these deficiencies by providing a valve which can be manufactured at relatively low cost, assembled with simplicity and which functions very effectively in a wide variety of logic circuits.

SUMMARY OF THE INVENTION A basic aspect of the present invention is a diaphragm valve, which can readily be used in a wide vareity of fluid logic circuits, and parts for this diaphragm valve, in particular a molded diaphragm and a pilot valve for controlling the operation of the diaphragm valve. Advantageously the pilot valve is controlled by a selected one of a plurality of control pressures, preferably three.

The invention will be described in conjunction with a number of embodiments of fluid operated valves, diaphragms and pilot valves for the valve, and various circuits utilizing a valve of the invention as shown and illustrated in the following drawings in which:

FIG: I is a vertical sectional view on a median plane through a preferred pneumatic NOR gate valve attached to a circuit board;

FIG. 2 is a semischematic vertical sectional view on the line 22 of FIG. 3 of a pneumatic NOR gate valve connected directly to fluid lines;

FIG. 3 is a top plan view looking down on the valve of FIG. 2 along the line 3-3 with part of the top wall being broken away and in crossection to show internal structure;

FIG. 4 is a bottom view on the line 4-4 of FIG. 2 with part in crossection;

FIG. 5 isa semischematic vertical sectional view on a median plane of a normally open two way valve including the diaphragm of the invention;

FIG. 6 is a semischematic vertical sectional view on a median plane of a normally closed dump valve including the diaphragm of the invention;

FIG. 7 is a semischematic vertical sectional view on a median plane of a pressure regulator including the diaphragm of the invention;

FIGS. 8 to 15 show the following schematic basic logic circuits using NOR gates of the invention in each of which a supply pressure line (not shown) is connected to the gate or gates of each figure to provide fluid (usually air) under pressure to each gate to flow out of the load line L at the apex of the gate under control of fluid pressure applied through a control port C:

FIG. 8 a NOR circuit;

FIG. 9 an AND circuit;

FIG. 10 a binary counter circuit; FIG. 11 a flip-flop or memory circuit; FIG. 12 a time delay circuit;

FIG. 13 a one-shot timer circuit; FIG. 14 a cyclic timer circuit; and FIG. 15 an oscillator circuit.

DETAILED DISCLOSURE OF, ILLUSTRATED EMBODIMENTS OF THE INVENTION Generally speaking the valve of the invention com- 1 prises a housing which has a cavity formed therein and a diaphragm located in the cavity which is held at its periphery in the housing to form one or more chambers which may be connected with passageways through the housing wall. The diaphragm carries (a) a passage closure element centrally thereof which is adapted, when the central portion is moved transversely of the diaphragm, i.e., up and down if the diaphragm is horizontal, to make and break communication between certain of these passageways, and (b) means for moving the central portion of the diaphragm transversely. In general the means for moving thecentral portion of the diaphragm for the opening and closing operation is a first class lever integral therewith which extends across the intermediate portion from the central portion toward the periphery. The term first class lever means a lever having its fulcrum at a point between its ends so that downward movement of one end lifts the other end and vice versa. An intermediate fulcrum is provided for the lever on the diaphragm so that force applied to the diaphragm in either direction outside of the fulcrum causes the inner end of the lever to move the central part of the diaphragm transversely thereof in the opposite direction. Preferably this lever comprises a plurality of rod-like elements extending radially across the intermediate portion of the diaphragm. The diaphragm is a molded structure made of suitable rubber or plastic material which has sufficient flexibility in thin sections to respond readily to the forces generated by differential pressures on opposite sides of the fulcrum and to provide relative rigidity in thicker sections of the passage closure element so as to make a satisfactory fluid tight seal against a suitable valve seat.

Referring now more particularly to FIG. 1, it illustrates a NOR gate. By NOR gate it is meant a valve which, when connected to a supply of air or other pressurized fluid will provide an outlet pressure signal unless a pressure signal is applied to one or any combination of control ports. The pneumatic NOR gate is adapted to be used as the basic logic element in circuits used to control the movement of pneumatic actuators which operate many types of machinery used in combination with sensors, manual valves, timers and other NOR gates to perform such functions as safety interlocks, counting, positioning, decision making, etc., and which may be performed without interfacing to electrical, electronic, or fluidic circuits, although such interfacing may be effected if desired.

The NOR gate illustrated in FIG. 1 comprises a housing 1, a top closure member 3, a diaphragm valve 5, a pilot valve 7 and a control board 9. It will be described for convenience with the valve in horizontal position as shown, but it will be understood that the valve may be used in any position so that what is described as the top closure may, in use, be at the bottom or side of the valve.

The housing 1 in this embodiment of the invention comprises a cup shaped base 2 having a bottom wall 4, a side wall 6, a plane top edge 8, an upwardly facing internal shoulder 10, a vent or vents 12 in the bottom wall 4, an antechamber 14 connected with the vents, a passageway 16 communicating with the antechamber 14 off center, and an atmosphere chamber 18 located in the cavity within the housing in contact with the lower surface of the diaphragm 5. Centrally of the upper side of the bottom wall 4 is a gasket 20 mounted in a recess 22 which positions the gasket for its function described hereinafter. The housing may be provided with struts 23 to strengthen the bottom and side walls and thereby minimize the amount of plastic or the like that is required to form a housing of sufficient strength. These struts 23 are preferably spaced around the circumference of the cup-shaped housing along generally radial lines, as may be seen in FIG. 4.

The top closure member 3 has a plane top 30, preferably in the same plane as the top edge 8 when the housing is assembled, although the top edge 8 may be some what below the plane top 30 without interferring in any way with the operation of the valve. The side wall 31 of the top member 3 conforms in shape to the internal surface of the side wall 6 above the internal shoulder 10. At the lower edge of the side wall 31 a downwardly facing shoulder 32 is provided which is somewhat above the upwardly facing shoulder 10 on the side wall 6 to provide gripping contact with the periphery of diaphragm between them. Below the shoulder 32 is a side wall extension 33 spaced somewhat from the interior surface of the side wall 6 below the shoulder to provide space for, and optionally further contact with, the diaphragm. The bottom wall 34 of the top member 3 has an annular gasket 35 suitably held within a recess 36 which is preferably concentric with the vertical axis of the housing. Between the gasket 35 and the side wall 33 is an annular projection 37 on the bottom wall 34 which is provided with an annular groove 38. Between the gasket 35 and the annular groove 38 is a supply passage 39 having at the top wall 30 a supply port 40 of larger diameter which provides an upwardly facing shoulder 41. The supply passage 39 communicates with a supply pressure chamber 42 located inwardly of annular groove 38. A load passage 63 formed in the top closure member 3 communicates with the supply pressure chamber 42 within, and preferably concentric with, the gasket 35. At the outer end of load passage 43 is a load port 44 of large diameter providing an upwardly facing shoulder 45.

The diaphragm 5 is molded of suitable material, e.g., plastic, rubber and the like, and has a peripheral portion 51 shaped to conform to the inner surface of side wall 6 just above the shoulder 10. As noted above, the housing is preferably circular in crossection so that the periphery of the diaphragm 5 also preferably is circular and the periphery is tightly gripped when the housing is assembled between the shoulders 10 and 32 and between the walls 33 and 6 to form a fluid tight connection with the housing.

integral with the peripheral portion 51 of the diaphragm is an intermediate portion 53 which is flexible and capable of bending under forces generated by differential pressures on the opposite sides of the diaphragm. Integral with the intermediate portion 53 is an annular wall 54 molded to the upper side of the diaphragm and which, in assembled state, is held in fluid tight relation in the groove 38 and forms a partition between chamber 42 and a control pressure chamber described hereinafter. Partition 54 may simply have a pressure lit in groove 38 but preferably it is fixedly bonded to the walls of the groove with the aid of some form of adhesive or by a welding process.

Integral with the intermediate portion is a central portion 55 of the diaphragm which carries a valve element 56. In the embodiment of the invention shown in FIG. 1 the valve element 56 includes an annular upper valve seat 57 on the upper end of a hollow cylinder 58 having thicker walls than the intermediate portion 53 so as to make this cylinder relatively rigid. At the lower end of the hollow cylinder 58 is an annular lower valve seat 59. The diaphragm 5 is thus perforated to permit air flow through it and the cylinder 58 constitutes a transverse passageway within both valve seats 57 and 59.

As seen in FIG. I, valve seat 59 is adapted to form a pressure tight connection with the gasket 20 when cylinder 58 is at the lower end of the transverse movement of the central portion 55 of the diaphragm. The hollow in cylinder 58 is designated as passageway 60 which is aligned with passageway 43 in the top closure member The means for effecting movement of the center section 55 preferably includes a lever 61 molded radially on the diaphragm 5, conveniently on the side opposite the wall 541. The lever extends across the projection of wall 54 which forms a fulcrum 62 for the lever, i.e., the juncture of the wall 54 with the intermediate portion 53 of the diaphragm constitutes the fulcrum around which the lever 61 moves as a first class lever. Preferably the lever comprises a plurality of elongated radially arranged bars which are spaced so as to fit between the struts 23, as may be seen in FIG. 4. As will be seen readily from FIG. 1, when the outer ends of levers 61 are pressed downwardly the inner ends of the levers raise the central portion 55 pressing the valve seat 57 against the gasket 35 in fluid tight relation. In this raised position passageway 43 is isolated from the supply pressure chamber 42, but is connected with the atmosphere chamber I8 by way of passageway 60.

When the inner ends of the levers 61 are pressed downwardly by forces on the intermediate portion of the diaphragm within the annular wall 54, the cylindrical portion 58 seals passageway 60, isolating it from the atmosphere chamber 18 by contact of seat 59 with gasket 20, and opens the seal between valve seat 57 and gasket 35. The valve seat 57 is spaced from the passageway 60 by a pressure area 63 whereas the valve seat 59 immediately surrounds the passageway 60. The pressure area 63 is made possible by an enlargement 64 at the top of the cylinder 58.

The pilot valve 7 is located in a recess 71 in the top closure member 3 outwardly of load port 44. The recess 71 includes an upwardly facing shoulder 72. The recess is closed by a pilot valve closure element 73 having a plane top surface 74, preferably in the plane of the top surface 30 of the closure element 3 and forms a fluid tight contact with the wall of recess 71 when it engages shoulder 72. Beneath the pilot valve closure element 73 is a control pressure antechamber 75 which communicated through a control pressure passage 76 with the outside of the housing. Control pressure passage 76 is provided with a control port 77 of larger diameter that forms an upwardly directed shoulder 78. The bottom wall of the pilot valve closure element 73 has a spherical pivot 79 formed thereon and the closure member 73 has a spherical pivot 80 in an upper surface thereof which is spaced from and concentric with the spherical pivot 79.

Mounted in the chamber 75 is a pilot valve lever 81 having a spherical recess 82 concentric with the spherical pivot '79 and a spherical projection 83 to fit in the spherical recess 80 with which it also is concentric. A valve plug 84 is mounted in an end of the pilot valve lever 81 as seen in FIG. 1 so that with slight movement it can open and close passageway 76 as the pilot valve lever 81 moves around its spherical pivot. Chamber 75 communicates by a connecting passageway 85 with a control pressure chamber 86 formed between the intermediate portion 53 of the diaphragm and the bottom wall of top closure member 3 outside of the partition member 54. i

The control board 9 includes an inner apertured plate 91, a middle gasket plate 92 and an outer closure plate 93. The apertured plate 91 includes a supply pressure aperture 94 communicating with a supply pressure ply pressure passage 95 and in the logic schematics this supply pressure line is designated by reference letter S.

Apertured plate 94 is also provided with a load pressure aperture 96 which communicates with a load pressure passage 97 which, in turn, communicates with a load pressure line (not shown in FIG. 1). In the logic schematics and the various circuits the load pressure line is indicated by the reference letter L, with subscripts if more than one load pressure line is used in a particular circuit.

Apertured plate 91 is also provided with a control pressure aperture 98 which communicates with a control pressure passage 99 in the gasket plate 92 and it, in turn, is connected to a control pressure line (not shown in FIG. I) but in the logic schematics the control pressure line is designated by reference letter C, with subscripts if more than one control pressure line is used.

Preferably, and as shown in the embodiment of the invention illustrated in FIG. 1, a plurality of control pressure lines C is used. If only one control pressure line is used a pilot valve lever is unnecessary but in the preferred embodiment there are three control ports and associated passages located at the apices of a triangle. In this preferred form the valve lever is also triangular with a valve plug 84 at each apex and in such realtion to the valve seats at the lower ends of passageways 76 that if a flow of control air is established through any one of the three ports, the other two are automatically closed. This requires a spherical pivot as shown in FIG.

I. If only two control ports are used, a spherical pivot is not necessary since a simple pivot would function where there are only two control ports to be opened and closed but a spherical pivot is still a very convenient and satisfactory type of pivot even for only two valve seats. Each control pressure line can be essentially the same in structure as the one shown in FIG. 1 comprising a control pressure passage 76 connected with control pressure antechamber 75, a control pressure port 77, a control pressure aperture 98 and a control pressure passage 99, one of the other two control passages 99 being visible in FIG. 1.

Each fluid line in the control board 9 is connected, as indicated above, by a fluid line (not shown) to other equipment with which the logic device is used. Fluid tight relation of the apertures of apertured plate 91 with the passageways is maintained by O-rings I00 compressed between the plate 91 and the respective upwardly directed shoulders 41, 45 and 78.

The operation of the logic device shown in FIG. I will be explained on the assumption that a supply pressure line (not shown) is connected to supply passage 95 and that air is flowing from the supply pressure line through passage 39 into supply pressure chamber 42 where the pressure is sufficient to move seat 59 of valve element 58 into pressure tight contact with gasket 20. This permits the air to flow between valve seat 57 and gasket 35 out of passageway 43 into the load pressure passage 97 and through a load pressure line (not shown) to the equipment with which it is used.

Now, assume that a control pressure is imposed from a control pressure line (not shown) through control pressure passageway 99 which causes air to flow past valve plug 84 into the control pressure antechamber 75. As soon as the flow of this control pressure air is established past valve plug 84, the pilot valve lever 81 is rocked on its spherical pivot to close the other one or two passageways 76, as the case may be, and thereby prevent escape of control pressure air through these other control passageways. The pressure in antechamber '75 is communicated through passageway to the control pressure chamber 86 where the pressure increases until the force on the intermediate portion of diaphragm 5 is sufficient to cause it to flex outwardly and thereby apply sufficient force to the inner ends of the levers 61 to lift the valve element 58 by snap action to seat valve seat 57 in fluid tight relation against gasket 35, thereby isolating passageway 43 from the supply pressure chamber 42. Simultaneously the passageway 68 is placed in communication with the atomsphere chamber I8 thereby venting the load pressure line to the atmosphere through passageways 60, I6 and 12.

Referring now to FIGS. 2, 3 and 4, the valve illustrated here hasessentially the same structure as the valve illustrated in FIG. ll except that the supply, load and control ports are each connected directly to the respective fluid line instead of going through a control board. Full details of the structure of these valves are not disclosed but they may be essentially the same as shown in FIG. 1 and only the parts of these valves essential to an understanding of their structure and function have been given reference numerals. Attention is directed, however, particularly to FIG. 3 which shows in plan view the arrangement of the valve plugs 84 at the apices of the triangular shaped pilot valve lever 81 and the location of the control pressure lines C and C to the third control pressure line (not shown in FIG. 3 but seen in FIG. 1 and which is above the plug 84 shown in full line inv FIG. 3). Attention is also directed to FIG. 4 which shows the location of three of a plurality of four passageways 12 in the bottom wall 4, a fourth (shown in FIG. 3) not being visible in FIG. 4 because the bottom wall 4 is broken away to show the relation of the strengthening struts 23 to the elongated levers 61 which may be located between these struts as illustrated. The number of these struts may be varied as needed and there need not be one between each pair of adjacent bars 61. The operation of the valve of FIGS. 2, 3 and 4 is the same as described for the valve of FIG. 1.

Referring now to FIG. 5, the structure of a normally open two way valve is illustrated which utilizes the diaphragm of the invention. In this embodiment of the invention the housing 2 does not include the cup-shaped base member because an atmosphere chamber is not essential in this embodiment of the invention. In this normally open two-Way valve the diaphragm is suitably secured in pressure tight relation at its periphery to the lower wall of the top element 3 in any suitable way. The upper wall of element 3 is provided with a supply pressure line S, a load pressure line L and a control pressure line C. Lines S and L communicate with a supply pressure chamber 42 and a gasket 35 of annular shape is provided around the load pressure line L. On the upper surface of the diaphragm S in the central portion thereof is a projection which forms a valve seat 57 on the upper surface adapted to seat against the gasket 35. In this embodiment the diaphragm is imperforate, i.e., there is no perforation or passageway through diaphragm 5 within the central portion, as there was in the embodiments of FIGS. 1-4 which represent perforate diaphragms. The diaphragm 5 is provided with an annular wall 54 forming a pressure tight partition between the supply pressure chamber 42 and the control pressure chamber 86 that communicates with the control pressure line C. Also formed on the diaphragm is one or more levers 61 with intermediate fulcrums at 62.

In the operation of this valve, when no control pres sure air flows through line C, supply pressure air flowing into chamber 42 through passageway S has free access across valve seat 57 into the load pressure line L. When a force is imposed on the outer ends of levers 61 by air flowing under pressure through line C, the central portion of the diaphragm is moved transversely by snap action to close in pressure tight relation the valve seat 57 against gasket 35 and thereby isolate the supply pressure line from the load pressure line. When the force exerted on the diaphragm in chamber 86 decreases until it is less than the force exerted in chamber 42, the central portion of diaphragm 5 snaps downwardly and again permits air to flow from S through L.

Referring next of FIG. 6, a normally closed dump valve is schematically illustrated in which the housing 2 includes a bottom wall 4 providing a plurality of passageways 12 connecting the atmosphere to an atmosphere chamber 18 and a support for a gasket 20 centrally of the lower wall. The diaphragm 5 is suitably mounted in pressure tight relation at its periphery to and in the housing to provide with the upper wall 3 thereof a supply pressure chamber 42; communicating with the supply pressure line S, a partition 54 between the supply pressure chamber 42 and a control pressure chamber 86 which communicates with a control pressure line C. Centrally of the perforate diaphragm 5 is a valve element 58 in the form of a hollow cylinder having a valve seat 59 at the lower end thereof which established fluid tight relation with the gasket 20 when the central portion of diaphragm S is depressed.

In operation of the normally closed dump valve, air under pressure is supplied to the supply pressure line S which generates sufficient pressure in the supply pressure chamber 42 to establish fluid tight contact of the seat 59 valve element 58 with gasket 20 so that under normal operating conditions this dump valve is closed. If control air under sufficient pressure is supplied through a control pressure line C, the force generated against the upper surface of diaphragm 5 at the bottom of control pressure chamber 86 is sufficient to overcome the force exerted against the diaphragm in chamber 42. At that instant lever 61 moves around fulcrum 62 to lift the valve element 58 by snap action and permit the supply pressure line L to be dumped through atmosphere chamber 18 and passages 12 to the atmo sphere.

Referring now to FIG. 7, this pressure regulator comprises a housing 2 having a load pressure line L communicating with a control pressure chamber 86 formed in the cavity of the housing by a diaphragm 5 which makes fluid tight communication at its periphery with the side wall of the housing. A supply pressure line S has a valve seat 59a formed at the end thereof communicating with the chamber 86. The valve element carried by the central portion of the diaphragm includes a gasket 56a adapted to make fluid tight contact with the valve seat 59a when the central portion of the diaphragm is raised. The imperforate central portion of the diaphragm 5 is biased to open position by a tension spring 65 connected at one end to the central portion of the diaphragm and at the other end to the bottom of a projection 66 formed in the lower wall 4 of the housing. In the bottom wall 4 a fulcrum 62a is formed which contacts the intermediate portion of the diaphragm 5 between the ends of the lever elements 61 that may be molded into the diaphragm at either side, being shown here on the upper side.

In operation, the air from the supply pressure line S is introduced into chamber 86 from which it flows through line L as long as the central portion of the diaphragm is held clear of the valve seat 59a. It will be observed that the pressure in chamber 86 is applied over the entire surface of diaphragm 5 in this embodiment of the invention without the presence of a partition wall. The location of the valve closure element 56a to a valve seat 59a will depend, therefore, on the balance of the forces generated by the pressure of the air on the upper surface of the diaphragm and the tension exerted on the central portion by the spring 65. The area of the diaphragm outside the fulcrum 62a is made larger than the area of the diaphragm inside the fulcrum 62a and as a result the pressure in chamber 86 at some point will create a greater force against the outer part of the diaphragm 5 than the combined force generated by the air pressure and the tension of spring 65. When this point is reached the central portion of the diaphragm will be lifted by levers 61 to restrict flow to load line L until such time as the pressure falls below the critical point, whereupon the valve will open again.

FIG. 8 discloses a basic logic circuit using the NOR gate of the invention. In this figure, letter designations with subscripts C C and C represent three control pressure lines and letter designation L represents the load line. As noted above, the supply pressure line, while used with the valve, is not shown since the pressure on the supply pressure line is constant. Table I shows the relation of the pressure in the load line L in relation to the pressure on the control pressure lines. In this Table a-l' represents positive pressure, and hence As shown in the table, if the pressure is zero on all of the control pressure lines, the pressure in load line L is positive and air flows from the supply pressure line S through the load pressure line L. As soon as a sufficient control pressure is impressed on any of the control pressure lines, the valve element flips and the pressure in load line L falls to zero.

Referring now to FIG. 9, the circuit shown illustrates the use of three NOR gates marked I, II and III, respectively, to provide an AND gate. It will be understood that each of the valves schematically illustrated is constantly supplied with air under pressure from a supply pressure line (not shown). Table II shows the logic circuit in which valve] has three control pressure lines C C and C valve II has three control pressure lines C C and C with the load line from each of them connected separately to one of the control pressure ports of NOR gate III. The remaining control pressure line of NOR gate III is connected to an index pressure line X. Table II shows the relationship of the pressures on the various control lines in relation to the index pressure X and the load pressure line L.

TABLE II C,,C or C, C C or C X L All All 0 0 0 All 0 All 0 0 All 0 Any O 0 Any M10 0 0 Any Any 0 Any Any 0 there is pressure on any of lines C C or C as long as the pressure on index line X is also zero there is no pressure in load line L. The same is true if the pressure on line C C or C is zero but there is a positive pressure on any of control lines C C or C as long as the pressure in line X is zero. If there is a positive pressure on any of lines C C or C and on any of lines C C or C and there is no pressure on index line X, there is then pressure in load line L. Under this same condition on the C lines, however, if there is pressure on index line X, the load pressure in line L is zero. Those skilled in the art will recognize that this system provides an AND function.

The circuit of FIG. 10 illustrates how the logic valve of the invention can be used to provide a binary counter. This counter involves the use of six NOR gates referred to respectively as I, II, III, IV, V and VI. Valve I has one of its control ports connected to reset pressure line R, another connected to the load line of valve Ill and the third connected to the load line of valve ll. Valve II has one of its control ports connected to a SET line, another connected to the load line L, of valve 1, and the third connected to the load line of valve IV. Valve III has its load line connected to load line L, which is also connected to one of the control ports for valves IV and V. One of the other control ports of both valves IV and V is connected to a trigger pressure line T which receives a pressure pulse from some outside valve that would give a pulse every time some event happened. For examplef the circuit of FIG. 10 may be used to count the number of bottles on a conveyor belt that move past a control point and the outside valve would give a pulse each time a bottle moved past it on the conveyor belt. Valve III has its other control pressure line connected to load line L, of valve IV. Valve IV has one control port connected to the load line from valve III as does also valve V. Valve V has one control port vented, and its remaining control port is connected to load line L,. Valve VI has one-control pressure port vented and its remaining control port is connected to load line L Table III shows the sequence of the operation to supply air under pressures to one or more of load lines L L L and L depending upon the pressure pulse on trigger line T.

The circuit of FIG. 10 is conditioned for operation by putting a pressure on the set line, it being understood that each valve is constantly supplied with air under pressure through a supply pressure line, not shown. Thereafter if there is not pulse on trigger line T there is flow of air through lines L, and L but none through L or L When a pressure pulse passes through trigger line T, L remains open but L closes and L and L remain closed. When this pressure pulse on line T terminates, the pressure on L falls to zero, air is supplied to lines L and L causing fluid to flow through them while L remains closed. At the next trigger pulse L and L remain closed. L closes and L remains positive with air flowing. When this trigger pulse ends, the system is restored to the initial condition set by control pressure on the SET line. The reset line R is for the same purpose as the SET line but to reverse the operation of the gates l and II. Those skilled in the art will recognize this as a binary counter.

Referring now to FIG. 11, this flip flop memory circuit involves the use of two NOR gates marked 1 and II. Valve I has two control pressure lines C and C connected with other valves (not shown) for providing pressure on one or the other of these lines. The third control pressure line of valve l is connected to the load line L of valve II. The load line of valve I is connected to load line L and to a control port of valve II, the other two control pressure lines C and C thereof being connected to other valves for providing pressure on one or the other of these control pressure lines. The load line from valve II connects to load line L and also to a control port of valve I as stated.

The sequence of operations in the flip flop or memory circuit of FIG. 11 is given in Table IV.

Referring now to FIG. 12, this time delay circuit includes two NOR gates designated as I and II. Each valve has two of its control ports vented and the control pressure line C has installed therein a volume chamber VC and a restricted passageway B. This restricted passageway acts as a resistor which slows up the flow of air into the volume chamber and thereby imposes a measurable time factor on the pressure build up to a level sufficient to flip the diaphragm with its control valve element in valve II. In the operation of this time delay circuit, when pressure is imposed on control line C, the air flows slowly through restricted passageway B until pressure builds up in the volume chamber VC to a sufficient level to cause the valve closure element in valve II to stop the flow of supply air through it from the supply pressure line (not shown) and into the open control line of valve I. When valve II, however, isolates its supply pressure from its load line, valve I will flip and permit air from its supply line (not shown) to flow through L This condition will remain until the control pressure on line C is cutoff, at which time the control pressure on valve I drops to zero, permitting its valve to flip to the original state and restore valve I to original state also.

Referring now to FIG. 13, the one-shot timer disclosed comprises the use of two NOR gates I and II. Gate 1 has one of its control ports vented, another connected to the load line of NOR gate II and the other connected through a volumn chamber and restricted passage to its load line L. Valve II has one of its control ports vented, another connected to Line L of valve I and the third connected to a control pressure line C. When a pulse is impressed on valve II through control pressure line C, the timer holds line L open until sufficient pressure is built up in volumn chamber VC through restricted passage B to cause the diaphragm in valve I to flip and close load line L.

Referring now to FIG. 14, this cyclic timer also involves the use of two NOR gates marked I and II, respectively. Gate I has one of its control ports vented, another connected to the load line L of valve II and the third connected to its own load line L, through a volumn chamber VC, and restricted passage 8,. Valve II has one of its control ports vented, another connected to the load line L, of valve I and the third connected to its own load line L through a volumn chamber VC and a restricted passage B The operation of this system is the same as the operation as the one-shot timer except that it automatically reverses after a predetermined period controlled by the size of the restricted passageway B, and B This system can be made very accurate through the use restricted passageways controlled by needle valves.

Referring now to FIG. 15, this oscillator involves the use of a single NOR gate having two of its control lines vented and the third connected to its load line through two restricted passageways B, and B and volume chambers VC, and VC connected in series. When supply pressure is connected to the NOR gate through its supply line (not shown), air will flow through load line L until the air pressure has built up in volume chamber VC, from VC, which builds gradually through B, and then flows gradually also through E, into VC When the pressure on the diaphragm reaches the flip point, the valve controlled by the central part of the diaphragm isolates the supply pressure from load line L and vents load line L to atmosphere but this is a gradual loss of pressure in the control pressure chamber through the two restricted passageways B and B and their associated volume chambers VC and VC, gives a time delay for the reversal and reestablishment of the conditions at the start of the operation. This oscillation takes place automatically in predetermined time sequence depending upon the sizes of the restricted passageways B, and B which again can be made very accurate through the use of needle valves.

It will be understood that modifications and variations may be made in the structure of the valves and the circuits in which they may be used without departing from the spirit and scope of the invention as defined in the claims.

Having thus described and illustrated the invention, what is claimed is:

1. A valve comprising:

a. a housing having a cavity therein;

b. a diaphragm forming a chamber in said cavity, said diaphragm having:

i. a peripheral portion secured in fluid tight relation in said housing,

ii. a central portion having a passage closure element thereon,

iii. an intermediate flexible portion and iv. a lever extending radially across said intermediate portion having an inner end adjacent to said center portion and an outer end adjacent to said peripheral portion;

c. a fulcrum for said lever between the inner and outer ends thereof;

d. a passageway through said housing communicating with said chamber through an orifice closable by said passage closure element; and

e. means for applying force to the outer end of said lever to rock it on said flucrum to move the central portion transversely to open and/or close said pas sageway.

2. A valve as set forth in claim 1 in which said fulcrum is an annular projection on said housing.

3. A valve as set forth in claim 2 in which the area of the diaphragm outside the fulcrum is greater than inside it, the valve element is biased to open position, and the means for applying force to the outer end of said lever includes a second passageway through said housing communicating with said chamber through an orifice not closable by said passage closure element.

4. A valve as set forth in claim 1 in which said fulcrum is an integral annular wall on said diaphragm forming a fluid tight connection between said housing and diaphragm.

5. A valve as set forth in claim 4 in which said means for applying force includes a control pressure chamber outside said integral wall and a passageway through said housing communicating with said control pressure chamber.

6. A valve as set forth in claim 1 in which said passage closure element includes a projection forming a valve seat at one side of said diaphragm that surrounds said closable orifice in closed position.

'7. A valve as set forth in claim 6 in which said diaphragm is imperforate.

8. A valve as set forth in claim 6 in which said diaphragm is perforate.

9. A valve as set forth in claim 6 in which said diaphragm is perforate and has a valve seat at each side thereof.

10. A valve as set forth in claim 6 in which said diaphragm is perforate and has a valve seat at each side thereof in which the perforation is a transverse passageway therethrough within both of said valve seats.

11. A valve as set forth in claim 6 in which said diaphragm is perforate and has a valve seat at each side thereof in which the perforation is a transverse passageway therethrough within both of said valve seats, the valve seat at the annular wall side of the diaphragm is spaced from the passageway by a pressure area and the valve seat at the opposite side immediately surrounds said passageway.

12. A valve comprising:

a. a multipart housing providing an internal cavity between them,

b. a diaphragm having a peripheral portion clamped in fluid tight relation between two parts of said housing so as to divide said cavity into chambers,

said diaphragm including;

i. a relatively flexible intermediate portion,

ii. a central portion having a valve element thereon,

and

iii. a lever secured to said diaphragm radially across said intermediate portion,

c. means providing a fulcrum for said lever between its inner and outer ends at the opposite side of said diaphragm,

d. a fluid passageway connecting a chamber on one side of said diaphragm to the exterior of the housing so located as to be opened and closed by said valve element, ancl e. means for exerting variable forces on said diaphragm at opposite sides of said fulcrum to move said valve element to opening and closing position.

13. A valve comprising:

a. a housing,

b. a diaphragm secured at its periphery in said housing having a wall connected to an intermediate portion of said diaphragm and to said housing to form a supply pressure chamber inside said wall and a control pressure chamber outside said wall,

c. a supply passageway connected to said chamber,

d. a load passageway connected to said chamber,

e. a valve element on a central portion of said diaphragm adapted to make and break communication of said supply passageway with said load passageway,

f. a lever secured to the intermediate portion of said diaphragm extending transversely, said intermediate portion with said wall forming its fulcrum, and

g. a control pressure passageway connecting said control pressure chamber to the exterior of the housing.

14. A valve as set forth in claim 13 in which the control pressure passageway includes an antechamber having a plurality of passageways communicating to the exterior of the housing. and a pilot valve pivotally mounted in said antechamber having means for closing each passageway so related thereto that flow of control pressure fluid through any control pressure passageway closes all the remaining control pressure passageways.

15. A molded diaphragm comprising a peripheral portion, a central portion having a valve element thereon and a flexible intermediate portion; and a lever secured to said diaphragm radially across the intermediate portion adapted when provided with a fulcrum between its inner and outer ends to move said valve ele ment transversely of the diaphragm in both directions in response to changes in force exerted on said diaphragm at opposite sides of said fulcrum.

16. A molded diaphragm as set forth in claim 15 in which an annular wall is secured to said intermediate portion between the inner and outer ends of the lever and functions as the fulcrum for it.

17. A molded diaphragm as set forth in claim 15 in which said valve element includes a projection forming a valve seat at one side of the diaphragm.

18. A molded diaphragm as set forth in claim 15 in which said valve element includes a projection forming a valve seat at one side of the diaphragm, and the diaphragm is imperforate.

19, A molded diaphragm as set forth in claim 15 in which said valve element includes a projection forming a valve seat at one side of the diaphragm, and the diaphragm is perforate. v

20. A molded diaphragm as set forth in claim 15 in which said valve element includes projections forming a valve seat at both sides of the diaphragm and the diaphragm is perforate.

21. A molded diaphragm as set forth in claim 15 in whichsaid valve element includes a projection forming a valve seat at each side of the diaphragm and in which there is a transverse passageway therethrough within said valve seats.

22. A molded diaphragm as set forth in claim 15 in which said valve element includes a projection forming a valve seat at each side of the diaphragm and in which there is a transverse passageway therethrough within said valve seat, the valve seat at one side of the diaphragm immediately surrounding the passageway and the valve seat at the other side being spaced from said passageway by a pressure area.

23. A molded valve element comprising a relatively rigid cylinder with an axial passageway therethrough, an annular valve seat at one end of said cylinder immediately surrounding the passageway, an enlargement at the other end of said cylinder having an annular valve seat thereon spaced from said passageway by a pressure area, and a relatively flexible outwardly extending diaphragm connected at its central portion to said cylinder between and substantially inwardly from said valve seats and having a peripheral portion adapted to be clamped in a valve housing.

24. A molded valve element as set forth in claim 23 in which an annular wall is molded to the intermediate portion of said diaphragm between the central and peripheral portions on the same side as said pressure area.

25. A molded valve element as set forth in claim 24 in which there is a plurality of first clas levers molded radially to said diaphragm on the side opposite and extending across the projection of said annular wall.

26. A pilot valve comprising a housing having a plurality of inlet openings into a chamber and an outlet from the chamber, the inner end of each inlet opening having a valve seat, a lever pivotally mounted in said chamber having a closure element extending into such close proximity to each valve seat that flow of fluid through one inlet opening pivots said lever to close the other inlet openings.

27. A pilot valve as set forth in claim 26 in which there are three inlet openings at the apices of a triangle and the lever is mounted on a spherical pivot.

28. A fluid logic valve device comprising a housing including an atmospheric pressure chamber having a vent opening through the housing, a molded diaphragm forming one fluid tight wall of said atmospheric chamber including an integral valve element centrally thereof, said element having a fluid passageway therethrough and being movable to a closed fluid tight position against a wall in said atmospheric chamber to prevent fluid flow through said passageway and to an open position permitting such flow, a supply pressure chamber located centrally in said housing around said valve element having a supply port connectable to a fluid supply line and a load port aligned with said passageway connectable to a load line, said outlet port being closed to said supply pressure chamber when said valve element is in said open position to vent fluid from said load line, a control pressure chamber located peripherally in said housing around and separated from said supply pressure chamber by an integral wall on said diaphragm, a pilot valve chamber in said housing including at least one control port connectable to a control pressure line and a connecting passageway to said control pressure chamber, and a pivoted pilot valve element in said pilot valve chamber for opening and closing said control port.

29. A fluid logic device as set forth in claim 28 in which said housing has a plane wall in which all said ports are located.

30. A fluid logic device as set forth in claim 28 in which said pilot valve chamber has a plurality of control ports and said pilot valve element closes all other control ports when one supplies control pressure.

31. A fluidlogic device as set forth in claim 30 in which the number of control ports is three located at apices of a triangle and the pilot valve element is mounted on a spherical pivot.

32. A fluid logic device comprising:

a. a cup shaped housing having a vent opening in the bottom wall thereof and a shoulder in the interior of the side wall thereof,

b. a top wall member having a plane outer surface closing the open end of said housing and c. a molded diaphragm having a periphery clamped in fluid tight relation between said member and said shoulder, said housing, member and diaphragm forming internally,

d. an atmospheric pressure chamber at one side of the diaphragm between it and vent opening,

e. a central supply pressure chamber and a peripheral control pressure chamber at the other side of said diaphragm, said member having l. a supply port and a load port in said plane surface, communicating with said supply pressure chamber, and 2 a plurality of control ports in said plane surface communicating with said control chamber.

33. A fluid logic device as set forth in claim 32 in which the number of control ports is three at apices of a a triangle and a pilot valve element is mounted in the control chamber on a spherical fulcrum to close two control ports whenever the third is supplying control pressure.

34. A fluid logic device comprising a cup shaped housing having a vent opening in the bottom wall thereof and a shoulder in the interior of the side wall thereof, a molded diaphragm having a peripheral bead engaging said shoulder and forming an atmospheric pressure chamber between it and said bottom wall. a top wall member having a plane outer surface having a peripheral shoulder secured in said cup shaped housing in fluid tight relation to the periphery of said diaphragm, said top wall member having through the plane surface thereof a supply pressure port, a load pressure port, a pilot valve chamber and a closure therefor having therein a plurality of control ports, and a communicating passageway leading from said pilot valve chamber to the side of said top wall member opposite said plane surface, said top wall member having a groove in the surface opposite said supply and load ports but inside said communicating passageway receiving in fluid tight relation a partition molded integrally with said diaphragm and forming an inner supply pressure chamber between said top closure member and said diaphragm communicating with said supply and load pressure ports and an outer annular control pressure chamber between said top closure member and said diaphragm communicating with said pilot valve chamber through said communicating passageway, and a valve element pivotally mounted in said pilot valve chamber having control port closing means adapted to admit control pressure from one control port while closing all other control ports.

35. A fluid logic device as set forth in claim 34 in which the number of control ports is three and said pilot valve element is mounted in a spherical pivot.

36. A fluid logic device as set forth in claim 34 in which said diaphragm has molded centrally thereof a hollow tubular valve element aligned with said load port and a portion of said bottom wall adapted in one position to engage said bottom wall in fluid tight relation to prevent fluid flow through said element and in a second position to engage said top closure member in fluid tight relation around said load port to isolate it from said supply pressure chamber and vent the load line through said tubular valve element into said atmospheric pressure chamber and means on said diaphragm to move said tubular valve element from its first to its second position when the force on the diaphragm from said control pressure chamber overcomes the force on said diaphragm from said supply pressure.

37. A fluid logic device as set forth in claim 36 in which said tubular valve element moving means is a plurality of radial first class levers molded to the lower surface of said diaphragm with their fulcrums opposite said partition.

* =k a 4: a: 

1. A valve comprising: a. a housing having a cavity therein; b. a diaphragm forming a chamber in said cavity, said diaphragm having: i. a peripheral portion secured in fluid tight relation in said housing, ii. a central portion having a passage closure element thereon, iii. an intermediate flexible portion and iv. a lever extending radially across said intermediate portion having an inner end adjacent to said center portion and an outer end adjacent to said peripheral portion; c. a fulcrum for said lever between the inner and outer ends thereof; d. a passageway through said housing communicating with said chamber through an orifice closable by said passage closure element; and e. means for applying force to the outer end of said lever to rock it on said flucrum to move the central portion transversely to open and/or close said passageway.
 2. A valve as set forth in claim 1 in which said fulcrum is an annular projection on said housing.
 2. a plurality of control ports in said plane surface communicating with said control chamber.
 3. A valve as set forth in claim 2 in which the area of the diaphragm outside the fulcrum is greater than inside it, the valve element is biased to open position, and the means for applying force to the outer end of said lever includes a second passageway through said housing communicating with said chamber through an orifice not closable by said passage closure element.
 4. A valve as set forth in claim 1 in which said fulcrum is an integral annular wall on said diaphragm forming a fluid tight connection between said housing and diaphragm.
 5. A valve as set forth in claim 4 in which said means for applying force includes a control pressure chamber outside said integral wall and a passageway through said housing communicating with said control pressure chamber.
 6. A valve as set forth in claim 1 in which said passage closure element includes a projection forming a valve seat at one side of said diaphragm that surrounds said closable orifice in closed position.
 7. A valve as set forth in claim 6 in which said diaphragm is imperforate.
 8. A valve as set forth in claim 6 in which said diaphragm is perforate.
 9. A valve as set forth in claim 6 in which said diaphragm is perforate and has a valve seat at each side thereof.
 10. A valve as set forth in claim 6 in which said diaphragm is perforate and has a valve seat at each side thereof in which the perforation is a transverse passageway therethrough within both of said valve seats.
 11. A valve as set forth in claim 6 in which said diaphragm is perforate and has a valve seat at each side thereof in which the perforation is a transverse passageway therethrough within both of said valve seats, the valve seat at the annular wall side of the diaphragm is spaced from the passageway by a pressure area and the valve seat at the opposite side immediately surrounds said passageway.
 12. A valve comprising: a. a multipart housing providing an internal cavity between them, b. a diaphragm having a peripheral portion clamped in fluid tight relation between Two parts of said housing so as to divide said cavity into chambers, said diaphragm including; i. a relatively flexible intermediate portion, ii. a central portion having a valve element thereon, and iii. a lever secured to said diaphragm radially across said intermediate portion, c. means providing a fulcrum for said lever between its inner and outer ends at the opposite side of said diaphragm, d. a fluid passageway connecting a chamber on one side of said diaphragm to the exterior of the housing so located as to be opened and closed by said valve element, and e. means for exerting variable forces on said diaphragm at opposite sides of said fulcrum to move said valve element to opening and closing position.
 13. A valve comprising: a. a housing, b. a diaphragm secured at its periphery in said housing having a wall connected to an intermediate portion of said diaphragm and to said housing to form a supply pressure chamber inside said wall and a control pressure chamber outside said wall, c. a supply passageway connected to said chamber, d. a load passageway connected to said chamber, e. a valve element on a central portion of said diaphragm adapted to make and break communication of said supply passageway with said load passageway, f. a lever secured to the intermediate portion of said diaphragm extending transversely, said intermediate portion with said wall forming its fulcrum, and g. a control pressure passageway connecting said control pressure chamber to the exterior of the housing.
 14. A valve as set forth in claim 13 in which the control pressure passageway includes an antechamber having a plurality of passageways communicating to the exterior of the housing, and a pilot valve pivotally mounted in said antechamber having means for closing each passageway so related thereto that flow of control pressure fluid through any control pressure passageway closes all the remaining control pressure passageways.
 15. A molded diaphragm comprising a peripheral portion, a central portion having a valve element thereon and a flexible intermediate portion; and a lever secured to said diaphragm radially across the intermediate portion adapted when provided with a fulcrum between its inner and outer ends to move said valve element transversely of the diaphragm in both directions in response to changes in force exerted on said diaphragm at opposite sides of said fulcrum.
 16. A molded diaphragm as set forth in claim 15 in which an annular wall is secured to said intermediate portion between the inner and outer ends of the lever and functions as the fulcrum for it.
 17. A molded diaphragm as set forth in claim 15 in which said valve element includes a projection forming a valve seat at one side of the diaphragm.
 18. A molded diaphragm as set forth in claim 15 in which said valve element includes a projection forming a valve seat at one side of the diaphragm, and the diaphragm is imperforate.
 19. A molded diaphragm as set forth in claim 15 in which said valve element includes a projection forming a valve seat at one side of the diaphragm, and the diaphragm is perforate.
 20. A molded diaphragm as set forth in claim 15 in which said valve element includes projections forming a valve seat at both sides of the diaphragm and the diaphragm is perforate.
 21. A molded diaphragm as set forth in claim 15 in which said valve element includes a projection forming a valve seat at each side of the diaphragm and in which there is a transverse passageway therethrough within said valve seats.
 22. A molded diaphragm as set forth in claim 15 in which said valve element includes a projection forming a valve seat at each side of the diaphragm and in which there is a transverse passageway therethrough within said valve seat, the valve seat at one side of the diaphragm immediately surrounding the passageway and the valve seat at the other side being spaced from said passageway by a pressure area.
 23. A molded valve elEment comprising a relatively rigid cylinder with an axial passageway therethrough, an annular valve seat at one end of said cylinder immediately surrounding the passageway, an enlargement at the other end of said cylinder having an annular valve seat thereon spaced from said passageway by a pressure area, and a relatively flexible outwardly extending diaphragm connected at its central portion to said cylinder between and substantially inwardly from said valve seats and having a peripheral portion adapted to be clamped in a valve housing.
 24. A molded valve element as set forth in claim 23 in which an annular wall is molded to the intermediate portion of said diaphragm between the central and peripheral portions on the same side as said pressure area.
 25. A molded valve element as set forth in claim 24 in which there is a plurality of first clas levers molded radially to said diaphragm on the side opposite and extending across the projection of said annular wall.
 26. A pilot valve comprising a housing having a plurality of inlet openings into a chamber and an outlet from the chamber, the inner end of each inlet opening having a valve seat, a lever pivotally mounted in said chamber having a closure element extending into such close proximity to each valve seat that flow of fluid through one inlet opening pivots said lever to close the other inlet openings.
 27. A pilot valve as set forth in claim 26 in which there are three inlet openings at the apices of a triangle and the lever is mounted on a spherical pivot.
 28. A fluid logic valve device comprising a housing including an atmospheric pressure chamber having a vent opening through the housing, a molded diaphragm forming one fluid tight wall of said atmospheric chamber including an integral valve element centrally thereof, said element having a fluid passageway therethrough and being movable to a closed fluid tight position against a wall in said atmospheric chamber to prevent fluid flow through said passageway and to an open position permitting such flow, a supply pressure chamber located centrally in said housing around said valve element having a supply port connectable to a fluid supply line and a load port aligned with said passageway connectable to a load line, said outlet port being closed to said supply pressure chamber when said valve element is in said open position to vent fluid from said load line, a control pressure chamber located peripherally in said housing around and separated from said supply pressure chamber by an integral wall on said diaphragm, a pilot valve chamber in said housing including at least one control port connectable to a control pressure line and a connecting passageway to said control pressure chamber, and a pivoted pilot valve element in said pilot valve chamber for opening and closing said control port.
 29. A fluid logic device as set forth in claim 28 in which said housing has a plane wall in which all said ports are located.
 30. A fluid logic device as set forth in claim 28 in which said pilot valve chamber has a plurality of control ports and said pilot valve element closes all other control ports when one supplies control pressure.
 31. A fluid logic device as set forth in claim 30 in which the number of control ports is three located at apices of a triangle and the pilot valve element is mounted on a spherical pivot.
 32. A fluid logic device comprising: a. a cup shaped housing having a vent opening in the bottom wall thereof and a shoulder in the interior of the side wall thereof, b. a top wall member having a plane outer surface closing the open end of said housing and c. a molded diaphragm having a periphery clamped in fluid tight relation between said member and said shoulder, said housing, member and diaphragm forming internally, d. an atmospheric pressure chamber at one side of the diaphragm between it and vent opening, e. a central supply pressure chamber and a peripheral control pressure chamber at the other side of said diaphRagm, said member having
 33. A fluid logic device as set forth in claim 32 in which the number of control ports is three at apices of a a triangle and a pilot valve element is mounted in the control chamber on a spherical fulcrum to close two control ports whenever the third is supplying control pressure.
 34. A fluid logic device comprising a cup shaped housing having a vent opening in the bottom wall thereof and a shoulder in the interior of the side wall thereof, a molded diaphragm having a peripheral bead engaging said shoulder and forming an atmospheric pressure chamber between it and said bottom wall, a top wall member having a plane outer surface having a peripheral shoulder secured in said cup shaped housing in fluid tight relation to the periphery of said diaphragm, said top wall member having through the plane surface thereof a supply pressure port, a load pressure port, a pilot valve chamber and a closure therefor having therein a plurality of control ports, and a communicating passageway leading from said pilot valve chamber to the side of said top wall member opposite said plane surface, said top wall member having a groove in the surface opposite said supply and load ports but inside said communicating passageway receiving in fluid tight relation a partition molded integrally with said diaphragm and forming an inner supply pressure chamber between said top closure member and said diaphragm communicating with said supply and load pressure ports and an outer annular control pressure chamber between said top closure member and said diaphragm communicating with said pilot valve chamber through said communicating passageway, and a valve element pivotally mounted in said pilot valve chamber having control port closing means adapted to admit control pressure from one control port while closing all other control ports.
 35. A fluid logic device as set forth in claim 34 in which the number of control ports is three and said pilot valve element is mounted in a spherical pivot.
 36. A fluid logic device as set forth in claim 34 in which said diaphragm has molded centrally thereof a hollow tubular valve element aligned with said load port and a portion of said bottom wall adapted in one position to engage said bottom wall in fluid tight relation to prevent fluid flow through said element and in a second position to engage said top closure member in fluid tight relation around said load port to isolate it from said supply pressure chamber and vent the load line through said tubular valve element into said atmospheric pressure chamber and means on said diaphragm to move said tubular valve element from its first to its second position when the force on the diaphragm from said control pressure chamber overcomes the force on said diaphragm from said supply pressure.
 37. A fluid logic device as set forth in claim 36 in which said tubular valve element moving means is a plurality of radial first class levers molded to the lower surface of said diaphragm with their fulcrums opposite said partition. 